(2)氨的吸收 H3 B03+ H20[B(OH)4]+H+ HO HOB←OH HO Ka=58×1010 HBO,+Ho+NH NHB (oh)（2）氨的吸收 H3BO3 + H2O → [B（OH）4 ] - + H+ HO HO—B OH HO Ka=5.8×10-10 H3BO3 + H2O + NH3 → NH4B（OH）4